Torque-transmitting, variably-flexible, locking insertion device and method for operating the insertion device

ABSTRACT

A torque-transmitting, variably-flexible, locking insertion device includes a hollow body having a proximal end with an entrance for receiving an instrument, a distal end with a tip for protrusion of the instrument, and a handle to be gripped by an operator. A device locks the handle to and unlocks the handle from the instrument, which is at least partly disposed within the hollow body. A device transitions the hollow body between a relatively flexible condition and a relatively stiff condition. A method for operating a torque-transmitting, locking insertion device includes placing the instrument at least partly within the hollow body and locking the handle to and unlocking the handle from the instrument. The hollow body is transitioned between a relatively flexible condition and a relatively stiff condition.

BACKGROUND OF THE INVENTION

Field of the Invention

The invention relates to a torque-transmitting, variably-flexible,locking insertion device. The invention also relates to a method foroperating the insertion device.

Description of the Related Art

Prior art insertion devices of this general type cannot be connected toan instrument, such as an endoscope or a colonoscope, in such a manneras to be reliable and sufficiently torque-transmitting, while at thesame time being easily releasable therefrom and variably flexible. Theoperator of the device must have the ability to manipulate theinstrument when necessary with the insertion device and yet free theinstrument easily when necessary.

Devices produced by Spirus Medical, Inc. under the designationsEndo-Ease advantage, Endo-Ease discovery and Endo-Ease vista are lightlyengaged to and disengaged from a colonoscope and rotate independentlythereof. The devices have a spiral at the distal end to follow the lumenof the colon or small bowel when rotated and pushed forward. All threedevices have a fixed and predetermined greater flexibility at the distalend and lesser flexibility at the proximal end.

SUMMARY OF THE INVENTION

It is accordingly an object of the invention to provide atorque-transmitting, variably-flexible, locking insertion device and amethod for operating the insertion device, which overcome thehereinafore-mentioned disadvantages of the heretofore-known devices andmethods of this general type and which permit an operator of the deviceto easily and reliably lock the insertion device to and unlock theinsertion device from an instrument while varying stiffness.

With the foregoing and other objects in view there is provided, inaccordance with the invention, a torque-transmitting, locking insertiondevice. The insertion device comprises a hollow body having a proximalend with an entrance for receiving an instrument, such as a scope, adistal end with a tip for protrusion of the instrument, and a handle tobe gripped by an operator. A device locks the handle to and unlocks thehandle from the instrument, which is at least partly disposed within thehollow body. A device, which may be vacuum activated, transitions thehollow body between a relatively flexible condition and a relativelystiff condition.

With the objects of the invention in view, there is also provided amethod for operating a torque-transmitting, locking insertion device.The method comprises providing a hollow body having a proximal end withan entrance for receiving an instrument, such as a scope, a distal endwith a tip for protrusion of the instrument, and a handle to be grippedby an operator. The instrument is placed at least partly within thehollow body and the handle is locked to and unlocked from theinstrument. The hollow body is transitioned between a relativelyflexible condition and a relatively stiff condition, such as by vacuumactivation.

Thus, through the use of the invention, an operator of the insertiondevice can not only lock the device to and unlock the device from aninstrument, but can also transition the device between relativelyflexible and relatively stiff conditions, while applying torque andaxial movement to the instrument.

In accordance with another feature of the invention, the locking andunlocking device includes an actuator to be activated by the operatorfor locking the handle to and unlocking the handle from the instrument.The actuator may be a bobbin to be slid onto the handle by the operator.The locking and unlocking device may also include a clamping platedisposed within the actuator. The clamping plate is moved radiallyinwardly against the instrument and radially outwardly away from theinstrument by activating the actuator. This structure provides a simpleand easy to use locking device, which nevertheless delivers reliablelocking of an instrument while transmitting torque and advancingaxially.

In accordance with a further feature of the invention, the clampingplate includes a plurality of partial-plates, at least one springbiasing the partial-plates radially outwardly and detents integral withthe partial-plates. The detents are disposed in recesses in the actuatorin a non-actuated condition and slide out of the recesses and push thepartial-plates towards the instrument against a force of the at leastone spring into an actuated condition. A body tube is disposed partiallywithin the actuator and partially within the handle. The body tube hasslots formed therein within which the detents slide between the actuatedand non-actuated conditions. The handle has a collar limiting motion ofthe actuator into the actuated condition. Although the plates, detentsand springs are simple elements, they produce reliable locking betweenthe handle and the bobbin.

In accordance with an added feature of the invention, a corrugated tubetransmits torque from the proximal end toward the distal end. An innersleeve disposed within the corrugated tube prevents vacuum leakage andaids in insertion of the instrument. Tendons are disposed along thecorrugated tube within the hollow body for maintaining the hollow bodyin the relatively flexible and relatively stiff conditions.

In accordance with an additional feature of the invention, the hollowbody has an outer jacket, the tendons are at least partly disposedbetween the outer jacket and the corrugated tube, and the transitioningdevice applies suction between the outer jacket and the corrugated tubefor frictionally locking the tendons in place. The corrugated tubeprovides a certain inherent stiffness, which can be greatly increased bythe operator of the insertion device by locking the tendons between theouter jacket and the corrugated tube.

In accordance with yet another feature of the invention, a couplerdisposed within the handle defines a vacuum plenum volume therebetween.The handle has a vacuum inlet/outlet hole formed therein communicatingwith the vacuum plenum volume.

In accordance with yet a further feature of the invention, a slidingvalve encircles the handle and has a vacuum inlet/outlet formed thereinfor communicating with the vacuum connection. The sliding valve slidesbetween a position in which the vacuum inlet/outlet communicates withthe vacuum inlet/outlet hole and a position in which the vacuuminlet/outlet is sealed against the vacuum inlet/outlet hole. Thus, thevariation in stiffness is provided by simply applying and releasingvacuum when desired by the operator.

In accordance with a concomitant feature of the invention, vertebrae aredisposed along the corrugated tube, between corrugation peaks, forguiding the tendons. The vertebrae include at least one last vertebraclosest to the distal end. Each two of the tendons form legs of aU-shaped configuration passing through holes in the vertebrae and beinginterconnected by a crosspiece distally of the last vertebra. There maybe two last vertebrae between which the crosspiece is fixed. The tendonsmay vary in number along the hollow body for providing zones of varyingstiffness. The tendons float when the hollow body is in the relativelyflexible condition. The tendons are not in tension or compression whenthe hollow body is in the relatively stiff condition. The tendons arenot under tension in both the relatively flexible and relatively stiffconditions. The combination of the vertebrae and the tendons provideinherent stiffness to the degree desired, while permitting addedstiffness to be attained by the transitioning device.

Other features which are considered as characteristic for the inventionare set forth in the appended claims.

Although the invention is illustrated and described herein as embodiedin a torque-transmitting, variably-flexible, locking insertion deviceand a method for operating the insertion device, it is nevertheless notintended to be limited to the details shown, since various modificationsand structural changes may be made therein without departing from thespirit of the invention and within the scope and range of equivalents ofthe claims.

The construction and method of operation of the invention, however,together with additional objects and advantages thereof will be bestunderstood from the following description of specific embodiments whenread in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic, perspective view of a torque-transmitting,variably-flexible, locking insertion device according to the invention;

FIG. 2 is a perspective view similar to FIG. 1, showing a working lengthof the insertion device;

FIG. 3 is an enlarged, perspective view of the insertion device, showingdetails of a proximal end;

FIG. 4 is a fragmentary, further enlarged, top-plan view of the proximalend of the insertion device;

FIG. 5 is an even further enlarged, fragmentary, side-elevational viewof the proximal end of the insertion device;

FIG. 6 is a perspective view of the insertion device with an outerjacket removed;

FIG. 7 is a fragmentary, enlarged, side-elevational view of the proximalend and part of the working length of the insertion device with theouter jacket removed;

FIG. 8 is a view similar to FIG. 6, of the insertion device with a lockin an actuated condition;

FIGS. 9A and 9B are even further enlarged, fragmentary, elevationalviews of a distal end of the insertion device in which a locking ring isrespectively shown and omitted for clarity and in which the outer jackethas been removed;

FIGS. 10A and 10B are fragmentary, perspective views of the distal endof the insertion device in which the locking ring is respectively shownand omitted for clarity and in which the outer jacket has been removed;

FIGS. 11A, 11B and 11C are fragmentary, longitudinal-sectional views ofthe distal end of the insertion device with the outer jacket removed andrespectively showing two locking rings, one locking ring and no lockingring;

FIG. 12 is an exploded, perspective view of the insertion device;

FIG. 13 is a fragmentary, longitudinal-sectional view of the proximalend and part of the working length of the insertion device;

FIG. 14 is a greatly enlarged, fragmentary, side-longitudinal-sectionalview of a proximal section of the insertion device;

FIG. 15 is a fragmentary, top-longitudinal-sectional view of theproximal section of the insertion device;

FIG. 16 is a fragmentary, side-longitudinal-sectional view of theproximal end of the insertion device;

FIG. 17 is a fragmentary, top-longitudinal-sectional view of theproximal end of the insertion device in the actuated condition;

FIG. 18 is a fragmentary, top-longitudinal-sectional view of theproximal end of the insertion device similar to FIG. 17, in anon-actuated condition; and

FIGS. 19A, 19B, 19C and 19D are enlarged, fragmentary, perspective viewsof the proximal end of the insertion device respectively showing ahandle with a clamping plate, a body tube slid over the clamping plate,an end cap at the proximal end and a bobbin distally of the end cap.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the figures of the drawings in detail and first,particularly, to FIGS. 1 and 2 thereof, there is seen atorque-transmitting, variably-flexible, locking insertion device 1according to the invention having a working length. The insertion device1 has a hollow body with a proximal end 2 for manipulation by anoperator and for receiving an instrument 40 such as an endoscope or acolonoscope, shown in FIG. 13. The insertion device 1 also has a distalend 3 for insertion into a patient and for protrusion of the instrument.A handle 4 of the hollow body for control by the operator is disposed atthe proximal end 2. An outer jacket or sleeve 5 of the hollow bodyextends to a tip 6, which may be formed of rubber, at the distal end 3.As will be explained below, the handle 4 has an end cap 8, an actuatoror bobbin 9 for locking an instrument, a sliding valve or slider 10 anda forward stop 11. The handle 4 also has a vacuum connection or nipple12 for controlling stiffness of the device, as will be explained belowas well. A corrugated tube 15 in the region of the distal tip 6, whichis illustrated in other figures, extends to the coupler 35.

FIGS. 3, 4 and 5 are enlarged perspective, top and side views showingthe insertion device 1, from which the end cap 8, the actuator or bobbin9, the handle 4, the sliding valve or slider 10 with the nipple 12, theforward stop 1 and the strain relief retainer 7, can be seen moreclearly. FIG. 3 also shows the outer jacket 5 and the distal tip 6.

FIGS. 6 and 8 are perspective views of the entire insertion device 1 andFIG. 7 is a fragmentary side view of the proximal end and part of theworking length of the insertion device, in which the outer jacket 5 hasbeen removed. It can therefore be seen that the corrugated tube 15extends distally beyond the strain relief retainer 7 to the tip 6 andthat vertebrae 16 are clipped between several of the corrugations.Although only five vertebrae are shown in FIGS. 6 and 8, as many astwelve or more may be provided, depending on the working length and theapplication for which the insertion device is intended. The vertebraemay have slits formed radially therein to aid in slipping them over thecorrugated tube. The last vertebra in the distal direction is a lockingring or termination vertebra 17. Whereas FIGS. 6 and 7 show theinsertion device in the unlocked condition, FIG. 8 shows it in thelocked condition, which will be discussed in more detail below. FIGS. 6,7 and 8 also show staples or tendons 18 extended axially along the outerperiphery of the corrugated tube 15.

As is seen in the fragmentary side, perspective andlongitudinal-sectional views of FIGS. 9A and 9B, 10A and 10B and 11A,11B and 11C, the tendons or staples 18 are looped through holes or slits22 in the vertebrae 16 and the locking ring 17. The locking rings 17have been omitted in FIGS. 9B and 10B to show details of the tendons orstaples 18. The tendons or staples 18 have ends 19 extending proximally,as shown in FIG. 12. The tendons or staples 18 may be fixedly connectedto the locking ring 17, such as by adhesive, weldments or solder joints.However, FIGS. 9B and 11A, 11B and 11C show that the tendons or staples18 have a U-shape with legs passing through the holes 22 in thevertebrae 16 and cross pieces 20 disposed just distally beyond thelocking ring 17. It can be seen particularly clearly in FIG. 11A thatthe cross pieces 20 of the tendons or staples 18 are captured andprevented from migrating distally by two locking rings 17 between whichthe cross pieces H are sandwiched in a valley or trough between twopeaks or crests of the corrugated tube 15.

The number and location of the tendons or staples 18 and the vertebrae16 axially and circumferentially may be chosen in such a way as to varythe stiffness of the insertion device 1 in zones. For example, moretendons or staples 18 and/or more vertebrae 16 may be placed in one zonealong the working length than in another zone. The zone with moretendons or staples and/or vertebrae will be stiffer. Additionally, someof the tendons or staples may not extend over the entire working lengthand some may be fixed to vertebrae along the working length, all ofwhich also varies stiffness in zones. As the insertion device flexes,some of the tendons or staples which are not fixed to particularvertebrae slide in the holes or slits 22.

The exploded view of FIG. 12 and the assembled sectional view of FIG. 13show the end cap 8 at the proximal end, which surrounds a rear bushing16. It may be seen that a marker band 28 is disposed between theactuator or bobbin 9 and the end cap 8. A clamping plate 30, which isalso disposed within the actuator or bobbin 9, has three partial-plates31 a, 31 b, 31 c between which three springs 32 are disposed. A bodytube 33, having slots 51, is disposed distally of the clamping plate 30.

A coupler 35, having grooves 23 extended axially on the peripherythereof, carries a septum seal 37 and an O-ring 38 provides a sealbetween the coupler 35 and the handle 4, which is slid over the coupler35. Other marker bands 29 are disposed between the handle 4 and thesliding valve or slider 10 and the forward stop 11 is disposed over thedistal end of the handle 4. O-rings 24 provide a seal between the slider10 and the handle 4. An O-ring 34 is disposed between the forward stop11 and the handle 4. It may also be seen that a heat shrink tubing 39covers the coupler 35 and an inner liner or sleeve 36 is disposed withinthe corrugated tube 15. Moving distally, the corrugated tube 15 carryingthe vertebrae 16, the tendons or staples 18, the locking ring 17 and thedistal tip 6, is shown as well.

The inner sleeve 36 provides a surface over which the instrument 40 willpass smoothly within the corrugated tube 15. The corrugated tube 15 maybe formed of nylon or another suitable material. The inner sleeve 36 maybe made from a sheet of polyester film, which has an adhesive coating onone side. The inner sleeve 36 is rolled around an inflatable mandrel andheated in an oven, to form a bonded seam and is sealed to an innersurface of the corrugated tube 15. The corrugations of the corrugatedtube 15 have peaks and valleys, as mentioned above. As viewed fromwithin the corrugated tube 15, the inner sleeve 36 adheres to the peaksand extends somewhat into the valleys of the corrugations as dimples.Therefore, as the insertion device bends, the inner sleeve 36 staystight along the corrugations on the outside of the bend and crinkles atthe inside of the bend. The peaks and valleys of the corrugations alsoneed not be of equal length along the length of the corrugated tube 15.For example, 70% of the length may be peaks and 30% valleys or 80% ofthe length may be peaks and 20% valleys. These variations will add tothe adhesion of the inner sleeve 36 to the corrugated tube 15 and reducethe formation of dimples. However, a 50/50 corrugation ratio is shown inthe figures.

The outer jacket 5 may be formed of polyurethane or another suitablematerial which is similarly a flat sheet that is rolled and seamed. Theouter jacket 5 extends to the distal tip 6 and the inner sleeve 36terminates with the end of the corrugated tube 15, the ends of which are“cuffed” to allow attachment of components.

The sectional views of FIGS. 14 and 15 show greater detail of theconstruction of the slider or sliding valve 10 having the nipple 12. Theslider 10, which encircles the handle 4, has a sliding so-called tirevalve thumb grip 13 and is sealed thereto by the O-rings 24 which aredisposed in recesses 14 in the handle 4.

It may be seen that the handle 4 and the coupler 35 define an annularvacuum plenum volume 41 therebetween which extends in longitudinaldirection of the handle 4. The O-ring 2 provides a seal at the proximalend of the volume 41. A vacuum inlet/outlet hole or port 42 is formed inthe body of the handle 4 and communicates with the volume 41. Thesliding valve or slider 10 also has a vacuum inlet/outlet 43 for theconnection or nipple 12. When the slider 10 is slid toward an annularstop 44, the vacuum inlet/outlet 43 is not in alignment with the vacuuminlet/outlet hole 42. However, when the slider 10 is slid toward anannular stop 45, the vacuum inlet/outlet 43 and the vacuum inlet/outlethole 42 are aligned, providing communication between the connection ornipple 12 and the volume 41. Therefore, during operation, the slider 10is slid toward the stop 45 to apply vacuum to stiffen the hollow body.The slider 10 is slid toward the stop 44 to vent the vacuum toatmospheric pressure making the hollow body flexible again.

When vacuum is applied to the volume 41 in the manner described above,the outer jacket 5 and the corrugated tube 15 approach each other withthe staples or tendons 18 sandwiched and frictionally lockedtherebetween. Therefore, the vacuum connection or nipple 12 acts as adevice for transitioning the hollow body 4, 6, 35, 5, 36, between arelatively flexible condition and a relatively stiff condition throughthe application of a vacuum. As long as the vacuum is applied, theinsertion device 1 maintains it condition, whether flexed or straight.When it is desired to resume flexibility of the insertion device 1, thevacuum is vented or replaced by air at ambient or positive pressure.This causes the corrugated tube 15 and the outer jacket 5 to release thetendons or staples 18 and the corrugated tube 15 and allows the inherentstiffness of the corrugated tube 15 to place the insertion device 1 intoits normally flexible condition.

The tendons, staples or wires 18 are passive elements which are not intension at any time. The tendons or staples float within the hollow body4, 6, 35, 5, 36, 15 when it is in the flexible condition, except wherethey are fixed to the locking rings 17. The tendons or staples arefrictionally locked by the corrugated tube 15 and the outer jacket orsleeve 5 when the hollow body is in the stiff condition. However, inboth the relatively flexible condition and the relatively stiffcondition, the tendons or staples have no active control imposed on themand are not pulled or constrained.

As mentioned above, a comparison between FIGS. 6 and 8 reveals that theactuator or bobbin 9 in FIG. 6 is adjacent the end cap 8 in anon-actuated condition, while in FIG. 8 the actuator or bobbin 9 is inan actuated condition, in which it has been moved over an extension 47of the handle 4 and against a collar 48 of the handle 4. FIGS. 16 and 18also show the actuator or bobbin 9 in the non-actuated condition,whereas FIG. 17 shows the actuator or bobbin in the actuated condition,but in greater detail.

As is seen in FIGS. 12-13, 16-18 and 19A, 19B and 19C, the threepartial-plates or partial-shells 31 a, 31 b, 31 c of the clamping plate30 have detents 50 protruding therefrom. FIGS. 17, 18 and 19A, 19B and19C in particular show that the springs 32 bias the partial-plates andtherefore the detents 50 through slots 51 in the body tube 33 and intocorresponding recesses 52 in the inner peripheral surface of theactuator or bobbin 9 in the non-actuated condition. When a sliding,so-called tire valve thumb grip 53 of the actuator or bobbin 9 is pushedby the operator of the device and the actuator or bobbin is sliddistally toward the collar 48 of the handle 4, the detents 50 slide outof the recesses 52 against the force of the springs 32. This causes thepartial-plates 31 a, 31 b, 31 c to move toward each other radially andagainst the instrument 40, such as an endoscope or a colonoscoperepresented by a dot-dash line in FIG. 13, for holding the instrument inplace. When the actuator or bobbin 9 is slid proximally, the detents 50once again fall into the recesses 52 due to the force of the springs 32,so that the partial-plates 31 a, 31 b, 31 c move radially outwardly andrelease the instrument 40. Therefore, the actuator or bobbin 9 and theclamping plate 30 form a locking and unlocking device to be activated bythe operator for locking the handle 4 to and unlocking the handle 4 fromthe instrument 40.

FIGS. 16, 17 and 18 also show the septum seal or valve assembly 37 ingreater detail, as well as the end cap 8 which is inserted into theproximal end of the handle 1. End caps 8 with various sized openings maybe used in dependence on the instrument being used. The instrumentpasses through the hollow body and emerges at the distal tip 6. It maybe seen that the septum seal or septum valve assembly 37 has a diaphragm37′ resting in a recess in the coupler 35.

A comparison of FIGS. 19A, 19B, 19C and 19D also shows that in FIG. 19Amerely the handle 4 with the extension 47 and the collar 48 as well asthe partial-plates 31 a, 31 b, 31 c are shown, while the body tube 33has been slid over the partial-plates in FIG. 19B, the end cap 8 hasbeen added at the proximal end in FIG. 19C and the actuator or bobbin 9has been added distally of the end cap in FIG. 19D.

The insertion device is intended to be used in a manner similar to priorart devices. Therefore, the insertion device will be placed over theendoscope. The endoscope will then be inserted into the rectum. Theinsertion device will then be pushed in its flexible condition, tofollow the curvature of the scope. The insertion device will then bestiffened, allowing the scope to be pushed forward with less pressureexerted on the colon of the patient. This procedure can be repeateduntil the scope reaches the cecum.

An alternative use of the insertion device is to aid in small bowelendoscopy. The insertion device is placed over the endoscope. Theendoscope is inserted into the patient transorally, through the stomachand then partially into the small bowel. The insertion device is thenpushed in its flexible condition, to follow the curvature of the scope.The insertion device is then stiffened, allowing the scope to be pushedforward without the scope looping in the stomach.

Another use of the insertion device is for aiding in access to internalbody parts, such as the gallbladder, through an opening of an internalbody cavity, such as the stomach. The insertion device is placed overthe endoscope. The endoscope is inserted into the patient transorally,through the stomach and then up against the internal surface of thestomach. The insertion device is then pushed in its flexible condition,to follow the curvature of the scope. The insertion device is thenstiffened, allowing the surgeon to create an opening in the stomach wallwithout the scope looping in the stomach. Once the opening is created,the insertion device and the scope can be advanced outside the stomach.The insertion device can then be stiffened to create a stable platformto perform surgical procedures outside of the stomach. The insertiondevice could contain one or more features (i.e. balloons) for sealingthe outer periphery of the insertion device to the stomach wall toprevent gastric fluids from exiting the stomach.

We claim:
 1. A torque-transmitting, variably-flexible, locking insertiondevice, comprising: a hollow body having a proximal end with an entrancefor receiving an instrument, a distal end with a tip for protrusion ofthe instrument, and a handle to be gripped by an operator; a device forlocking said handle to and unlocking said handle from the instrument atleast partly disposed within said hollow body; a device fortransitioning said hollow body between a relatively flexible conditionand a relatively stiff condition; and tendons disposed within saidhollow body for maintaining said hollow body in said relatively flexibleand relatively stiff conditions, said tendons being neither in tensionnor compression when said hollow body is in said relatively stiffcondition.
 2. The insertion device according to claim 1, wherein saiddevice for locking said handle to and unlocking said handle from theinstrument includes an actuator to be activated by the operator forlocking said handle to and unlocking said handle from the instrument. 3.The insertion device according to claim 2, wherein said actuator is abobbin to be slid onto said handle by the operator.
 4. The insertiondevice according to claim 2, wherein said locking and unlocking deviceincludes a clamping plate disposed within said actuator, said clampingplate being moved radially inwardly against the instrument and radiallyoutwardly away from the instrument by activating said actuator.
 5. Theinsertion device according to claim 4, wherein said clamping plateincludes a plurality of partial-plates, at least one spring biasing saidpartial-plates radially outwardly and detents integral with saidpartial-plates, said detents disposed in recesses in said actuator in anon-actuated condition and sliding out of said recesses and pushing saidpartial-plates towards the instrument against a force of said at leastone spring into an actuated condition.
 6. The insertion device accordingto claim 5, which further comprises a body tube disposed partiallywithin said actuator and partially within said handle, said body tubehaving slots formed therein within which said detents slide between saidactuated and non-actuated conditions.
 7. The insertion device accordingto claim 5, wherein said handle has a collar limiting motion of saidactuator into said actuated condition.
 8. The insertion device accordingto claim 1, wherein said transitioning device is vacuum activated. 9.The insertion device according to claim 8, which further comprises acorrugated tube for transmitting torque from said proximal end towardsaid distal end.
 10. The insertion device according to claim 9, whichfurther comprises an inner sleeve disposed within said corrugated tubefor preventing vacuum leakage and aiding in insertion of the instrument.11. The insertion device according to claim 9, wherein said tendons aredisposed along said corrugated tube within said hollow body formaintaining said hollow body in said relatively flexible and relativelystiff conditions.
 12. The insertion device according to claim 11,wherein said hollow body has an outer jacket, said tendons are at leastpartly disposed between said outer jacket and said corrugated tube, andsaid transitioning device applies suction between said outer jacket andsaid corrugated tube for frictionally locking said tendons in place. 13.The insertion device according to claim 12, wherein said transitioningdevice includes a vacuum connection.
 14. The insertion device accordingto claim 13, which further comprises a coupler disposed within saidhandle and defining a vacuum plenum volume therebetween, said handlehaving a vacuum inlet/outlet hole formed therein communicating with saidvacuum plenum volume.
 15. The insertion device according to claim 14,which further comprises a sliding valve encircling said handle andhaving a vacuum inlet/outlet formed therein for communicating with saidvacuum connection, said sliding valve sliding between a position inwhich said vacuum inlet/outlet communicates with said vacuuminlet/outlet hole and a position in which said vacuum inlet/outlet issealed against said vacuum inlet/outlet hole.
 16. The insertion deviceaccording to claim 15, wherein said handle has a recess formed thereinreceiving an O-ring for sealing said sliding valve to said handle. 17.The insertion device according to claim 11, which further comprisesvertebrae disposed along said corrugated tube for guiding said tendons.18. The insertion device according to claim 17, wherein said vertebraeare disposed between corrugation peaks of said corrugated tube forguiding said tendons.
 19. The insertion device according to claim 17,wherein said vertebrae include at least one last vertebra closest tosaid distal end, each two of said tendons forming legs of a U-shapedconfiguration passing through holes in said vertebrae and beinginterconnected by a crosspiece distally of said last vertebra.
 20. Theinsertion device according to claim 19, wherein said at least one lastvertebra are two last vertebrae between which said crosspiece is fixed.21. The insertion device according to claim 11, wherein said tendonsvary in number along said hollow body for providing zones of varyingstiffness.
 22. The insertion device according to claim 11, wherein saidtendons float when said hollow body is in said relatively flexiblecondition.
 23. The insertion device according to claim 11, wherein saidtendons are not under tension in both said relatively flexible andrelatively stiff conditions.
 24. The insertion device according to claim1, wherein the instrument is a scope.